42x5y4=(-7x3y)(B)
B =
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Answer:
-5*x^2*y^3
Step-by-step explanation:
42*x^5*y^4/(-7*x^3*y)=B
42/-7 = -5
x^5/x^3 = x^2
y^4/y=y^3
so B = -5*x^2*y^3